L4 Cellular Cooperation and Cytokines - Hudig Flashcards
Where do you find MHC I?
all cells except red blood cells
What is the three step process for MHCI presentation?
cytoplasmic tagging (ubiquitin), degradation and presentation
T/F: both MHCI and MHCII present self peptides all the time even without infection
true
From what cellular compartment does MHC I get its proteins?
cytosol, that’s where viruses make their proteins
After ubiquitinating viral proteins and unfolding them, what size does the proteasome cleave them into?
8-11 aa’s
(blank) transports the proteins from the cytosol post-proteasome into the ER
TAP: transporter of antigenic peptides
Where is the Ag loaded onto the MHC I?
in the ER
Where does the AG-MHCI complex go after the ER?
to the Golgi
The golgi produces a (blank) vesicle which fuses with the PM to display the Ag-MHCI
exocytic vesicle
What size must proteins be to present on MHC II?
20-30 aa’s long
Where do you find MHC II cells
APCs, B Cells and endothelial cells
What cells types only express MHCII after induction?
B cells and endothelial cells
What is the main source of Ag for MHCII?
extracellular proteins
What is the three step process for Ag presentation on MHCII?
ingestion, degradation, and presentation
Bacterium, virus, or proteins are ingested into the (blank)
endosome
endosome fuses with the (blank) to form the phagolysosome
lysosome
T/F: extracellular virions are also presented on mHCII
true
where are the MHCII proteins made?
in the ER
Wher is the Ag-MHCII complex formed?
lysosome-golgi vesicle fusion
Describe the process of loading Ag onto MHCII ?
MHCII made in ER
MHC transported to golgi, packaged into exocytic vesicle
Lysosome containing degraded protein fuses with vesicle and forms Ag-MHCII complex
which T cell class is used to control chronic viral infections?
CD8
What must CTLs do before they can kill?
divide
What is the reason that T cells only recognize proteins?
only living things produce proteins; 4 nucleic acids have more variability than sugar; 20 aa’s give more ability to distinguish between self and nonself
What are the APCs of the skin?
Langerhan’s cells
what are teh APCs of the lymphoid organs?
dendritic cells
T/F: all tissue macrophages have TLRs that recognize LPS
true
T/F: tissue macrophages can detect bacterial DNA and ssRNA
true
What two cytokines do all tissue macrophages produce?
IL1 and TNF-a
Why are CTLs difficult to monitor for vaccine production?
- Each naive t cell has a unique TCR
- each t cell needs an EXACT match to the Ag-MHC complex to bind
- There are 1000s of different mHCI alleles
- to test CTL anti-viral vaccines you needs the target cells of the SAME MHCI allelle as the donor of the CTLs
HIV nef blocks (blank) synthesis
MHCI
Herpes simplex ICP47 blocks (blank) activity which prevents peptides to be transported from the proteasome into the ER
TAP
CMV H301 blocks what part of MHC function?
surface expression
What are the four cell types needed to cooperate to generate CTLs?
- APCs
- TFH
- TH1
- CTL
Explain the cell cooperation process of generating CTLs?
- APCs ingest Ags
- TFH TCR binds APC-Ag; releases IL2
- TH1: IL2 receptor, releases IFNg
- CTL: IFNg receptor; granule production
What are the three cells needed to make Abs?
- APC
- TH2
- B cell
Describe the cellular cooperation to produce antibodies?
- APC ingests Ag
- TH2: releases IL4;
- B cell: IL4 receptor; proliferates and secretes Ab
What cells produce TNF-a and IL1?
APCs
What cells produce IL2 and IFNg?
TH1
What cells produce IL4?
Th2
Why is route of vaccine administration important?
different Ig classes in different areas: mucosal vs IM vs IV
When would you use a live virus?
- if the virus spreads via syncytia
- cheaper
- ACTIVATES CD8 CTL
- Ag peptides are produced INTRACELLLARLY in the infected cell cytoplasm
- MHC I presentation of 8-11 aa’s
When would you use a heat killed virus?
- Safety is higher
- Stores better without refrigeration
- ACTIVATES CD4 TH1 if first exposure, TH2 if second exposure
How do APCs enter a lymph node?
afferent lymphatics
Where are the macrophages and plasma cells in the lymph node?
medullary cords
Where are the B cells in the lymph node?
germinal center/follicles
Where are the T cells in the lymph node?
paracortex
what happens to lymph node architecture in AIDS?
IT IS DESTROYED
What are the APCs of the lymph node?
dendritic cells
What is the APC of Peyer’s patches?
M cell; sits on the GI epithelium
Where are the b cells in PP?
in deeper follicles
Where are the T cells in PP?
area below the epithelium but above the follicles
How are Ags circulated from PP?
lymph drains to regional lymph nodes
T/F: Spleen has follicles containing B cells
true
Where are the T cells located in the spleen?
periarterioalr sheath of white pulpe (PAS)
What is the APC of the spleen?
DC
Are the DCs that present Ag to the T cells in the PALS the same as the DCs that activate the B cells in the spleen?
no
What kind of response do you get in a live attenuated or killed bacteria vaccine?
Ab response
What kind of response do you get in a live attenuated virus vaccine?
cell mediated and Ab
What kind of response do you get in a conjugate vaccine?
Helper t cell dependent ab response
What kind of response do you get in a synthetic vaccine?
Ab response
What kind of response do you get in a antigen vaccine?
Ab response
What kind of response do you get in a DNA vaccine?
cell mediated and humoral resposne
